Engine Wont Start(fuel pressure regulator?)

[Stringbean781]

Hello,

So I have a 1981 Fiat Spider 2000. Introduction post here...
http://www.fiatspider.com/f15/viewtopic ... 09#p283525

While waiting on the fuel pump, we were able to get her to idle on starting fluid(air filter box disconnect; spraying starter fluid at throttle valve).

We were able to replace the fuel pump and filter, but she still wouldn't start. Pump was working fine so we were attempting to check if fuel was getting to the fuel rail but the connection was completely stuck(soaking with break-in fluid now). We decided to check if the fuel rail was pressured by unscrewing the nut just to the side of the fuel pressure regulator. The fuel rail was pressured and spew out pressured gasoline. When we reconnected it and tried starting the engine, it fired and ran for 3 seconds before shutting off again(didn't start after that), we depressurized the rail again by disconnecting and reconnecting the same nut. The engine fired and ran again for 3 seconds, then wouldn't start after that.

I am an engineer, but I am no mechanic. My assumption is that the pressure regulator is not decreasing the pressure from the fuel pump. The car runs until the pressure reaches that of the fuel pump and it dies. I was curious if this is the case, and if anyone could help me on this subject.

Thanks,
Jack McDonald

[Spider951]

Could be so many things with a car that sat that long, e.g. fuel injectors, spark plugs, fuel lines, etc. Give us more info on what you have checked, cleaned, and/or replaced. There are lots of people here who know way more than I do about Fiats.

[Spider951]

Also...... it's likely the timing belt needs to be changed (probably sooner rather than later).

And it will likely help to read about Bosch L-Jetronic fuel injection - do a search for Brad Artigue's guide (and other good info on this site). Some EFI sensors may need replacing.


Steve

[RRoller123]

Here is my "go to" list of FI references, to supplement Brad's excellent work:

FUEL INJECTION DEBUGGING
http://www.hiperformancestore.com/Ljetronic.htm
http://www.njfiats.org/joomla/images/st ... BoschL.pdf

FUEL INJECTOR CLEANING:
WWW.OKINJECTORS.COM
www.witchhunter.com

FUEL INJECTION MANUAL
http://www.mirafiori.com/faq/fiatFI_may2002.pdf

FUEL INJECTORS CHART
http://users.erols.com/srweiss/tableifc.htm

L-JETRONIC MANUAL
http://www.hiperformancestore.com/Ljetronic.htm

L-JETRONIC
http://mastertechmag.com/pdf/1988/11nov ... ronic2.pdf
http://jenniskens.livedsl.nl/Technical/ ... tronic.pdf

L-JETRONIC FI MANUAL (FROM VW)
https://www.type4.org/manuals/ljet/index.html

BOSCH L-JETRONIC MANUAL – BEST ONE:
http://foxed.ca/rx7manual/manuals/BOSCH ... Manual.pdf

[kmead]

If it will start and run for three seconds it means that the cold start injector is working. It is only designed to work for a limited period of time.

That it won’t continue to run means that either the injectors are not receiving a signal to open and close or they are stuck closed which wouldn’t be unusual on a car left unused for a long time.

You should buy a ‘noid’ test light to verify that the injectors are receiving signal. You don’t want to use a test light as you could damage your injection system ECU.

Download and work through this manual: https://www.dropbox.com/s/xeg7c78cjbkec ... p.pdf?dl=0

Once you run through the various diagnostics you will know if you need to pull the injectors and have them cleaned/replaced or if it is something else in the chain of parts which is getting in the way of the engine running.

Karl

[RRoller123]

You can also listen to the injectors with a mechanic's stethoscope, and clearly hear them clicking if they are working. Nice little diagnostic aid. HF has them for a couple of bucks.

[Stringbean781]

Thank you so much for all the replies! That Debugging pdf looks like it will be very useful in helping me to get it running. I’m positive the fuel/injectors are mechanically good. Have changed fuel tank, and fuel lines, most vacuum hoses etc. Will be checking for electric pulses to the injectors.

I also found a black+pink and black+white wire underneath the drivers seat separated from each other and not connected to anything. I’ve looked at the wiring diagrams and cannot figure out what this is for.

Also, would love to post some images of the car but i am unsure how to on this forum.

Thanks again!

[DRUMMOND]

Make sure you are getting power to your injectors. disconnect number one injector, should show 12v. If not check that your double relay is working.
If getting 12v check that your ignition coil ground wire to the ECU is working, this provides the signal for the ECU to fire the injectors.

To check each injector go get a connector pigtail ,connect one at a time to 12v + then ground the other lead, you will hear the injector click this will verify at least they are working no click means they are stuck closed.



Drivers seat wire is probably the seat belt warning chime that has been disconnected.

[RRoller123]

There are 2 ground wires that attach to the two rearward, driver's side air plenum top mounting bolts by ring terminals. If they are loose or not connected, the ECU will not fire the Injectors. Check these carefully too.

[Stringbean781]

we got her running!!! Purrs like a kitten!!! Ended up being a bad distributor pickup wire I believe. Replaced that, distributed vacuum regulator, fuel system, timing belt, water pump, air flow meter, and a couple other small parts. Finishing up body work and interior now!

A few things that still need fixing.
There seems to be a small oil leak on the right cam cover that drips onto exhaust producing smoke.

The fabric top framing is good except for where it connects to the windshield(rusted out). I have seen fiat spiders with a hard top and would be interested in that but can’t seem to find a hard top conversions for sale anywhere.

Thanks for the help you guys have given!! Greatly appreciated!

[kimu]

Good to hear that you got it going...If the distributor pickup fixed the "running for three second" issue, why did you feel the need to replace the Air Flow meter? Just curious.

I am fighting the same problem with my 82.

Thanks..

[Stringbean781]

@kimu
During the trouble shooting phase, I followed the troubleshooting manual testing different components with my multimeter. I could tell that the plastic square cover on the MAF meter had been tampered with before. When I did the resistance tests, they did not match what the Troubleshooting manual suggested so we purchased a refurbished one. I forget the exact manual but a member posted the link earlier in this thread.

[wizard124]

A few things that still need fixing.
There seems to be a small oil leak on the right cam cover that drips onto exhaust producing smoke.

Thanks for the help you guys have given!! Greatly appreciated!

Look closely at the leak. The exhaust manifold studs penetrate too deep and can leak oil; second one from the front on mine.
I used JB weld for a fix. Applied directly to stud threads.

[Stringbean781]

A few things that still need fixing.
There seems to be a small oil leak on the right cam cover that drips onto exhaust producing smoke.

Thanks for the help you guys have given!! Greatly appreciated!

Look closely at the leak. The exhaust manifold studs penetrate too deep and can leak oil; second one from the front on mine.
I used JB weld for a fix. Applied directly to stud threads.

Thank you! I will take a look into that!

[rridge]

from the Bosch L-jetronic Diagnostic Manual:
Page 1, paragraph one
Starter Runs, Engine Will Not Start
Step 1 - Check Ignition System

When a fuel injected engine doesn't start the impulse is almost always to start work on the fuel side, the complicated side that we do not understand. However, running on starter fluid but not on gasoline proves only that starter fluid is easier to ignite. It takes only a few minutes to check for a fat spark by disconnecting a spark plug wire and connecting it to spare plug that has been grounded.